Mature cystic teratoma of the neck misdiagnosed at cystic hygroma; Case report

Congenital mature cystic teratoma of the parotid gland in an infant: Report of a unique case

INTRODUCTION AND IMPORTANCE

Teratoma is a germ cell tumor originating from pluripotent germ cells and embryonal cells that commonly occurs in the gonads with only 15 % of it arising in extragonadal sites. In infants and children, teratomas of the head and neck are uncommon that comprise 0.47 %-6 % of all teratomas, and their occurrence in parotid gland is extremely rare. It is considered a diagnostic pitfall preoperatively, and their definite diagnosis can only be made upon surgery followed by histopathological examination.

CASE PRESENTATION

We present a unique case of parotid gland teratoma in a 9-month-old girl who was brought to the hospital by her parents with right side parotid region swelling since birth. The ultrasonographic findings were suggestive of cystic hygroma. Upon surgery, the mass was completely excised with a part of parotid gland. The diagnosis of mature teratoma was made based on the histopathologic examination. No tumor recurrence was noted during the 4-month postoperative follow-up.

CLINICAL DISCUSSION

Teratoma of the parotid gland is an extremely rare entity that may mimic diverse benign and malignant tumors of the salivary gland. Patients often present to the health care facility with a parotid gland swelling leading to defacement. Complete surgical resection of the tumor is considered the best treatment approach with careful preservation of facial nerve.

CONCLUSION

Due to the scarcity of information available regarding the behavior and clinical management of parotid gland teratoma in the literature, a good follow-up of patient is required to exclude potential recurrency and neurological deficit.

Distinctive clinical and pathologic features of immature teratomas arising from induced Pluripotent Stem Cell-derived beta cell injection in a diabetes patient

Induced pluripotent stem cells (iPSCs) are a new potential cure for diabetes, characterised by a capacity for self-renewal and differentiation to pancreatic islet beta cells, which secrete insulin and rebuild blood glucose balance. The safety and validity of iPSC-derived cell therapy for diabetes remain controversial. Teratoma formation arising from undifferentiated stem cells is a serious risk, but clinical reports of this phenomenon are rare. Here, we report a distinctive case of immature teratoma after the patient underwent iPSC-derived cell therapy for diabetes in another hospital, and he wastreated in our soft tissue sarcoma centre. The patient received islet beta cell injection, in which the cells were differentiated from autologous iPSCs, into the deltoid muscle. Two months later, a mass located in the injection area was detected and presented with enlarged axillary lymph nodes. Here, we present the clinical, radiological, and pathological features of this immature teratoma. Distinct from typical immature teratomas, this tumour was characterised by rapid growth and local lymph node metastasis. The tumour did not respond to typical chemotherapy regimens for immature teratomas. Magnetic resonance imaging (MRI) showed heterogeneous enhancement and a rich blood supply to the tumour. Histopathology revealed immature endoderm, mesoderm, and ectoderm tissues composed of osseous, cartilaginous, vascular, and adenoid tissues, which have more cellular atypia than typical teratomas. Staining for both OCT4 and SOX2 was positive in the tumour cell nucleus as revealed by immunofluorescence assay; however, insulin staining was negative. Next-generation sequencing showed many missense mutations, but abnormal gene rearrangement, defects, or changes in copy numbers were not observed. In conclusion, more attention should be given to teratoma formation after iPSC-derived cell therapy for diabetes, because these tumours are more aggressive than typical teratomas. The safety and validity of iPSC-derived cell therapy for diabetes should be explored further in standardised clinical trials.

Cervical Cystic Teratoma: An Unusual Cause of Airway Obstruction in the Pediatric Population

Cystic teratoma is a germ cell tumor, which usually involves the gonads. However, it can be located occasionally in other organs. The most common extragonadal sites for germ cell tumors include midline structures such as the retroperitoneum, mediastinum, pineal body, and supra-sellar space. Here, we describe a case of a patient who presented with a cystic teratoma involving the anterior aspect of the neck. The chief complaints of the patient consisted of a large swelling in front of the neck, difficulty in breathing, and frequent regurgitation of milk during feeding. Initially, a diagnosis of cystic hygroma was instituted for which the patient underwent sclerotherapy utilizing bleomycin. However, no improvement was observed in the patient's condition. A detailed evaluation was planned, starting with a CT scan of the head and neck that suggested cystic teratoma as the likely etiology. Surgical excision of the mass was performed, and an excisional biopsy for histopathological examination was taken. A final diagnosis of cervical cystic teratoma was established based on the histopathological findings. The purpose of reporting this case is to raise awareness among fellow healthcare professionals that cystic teratoma can also present with a large swelling in the anterior neck with obstructive features.